A parametrized diamond principle and union ultrafilters
Logic
2018-08-13 v2
Abstract
We consider a cardinal invariant closely related to Hindman's theorem. We prove that this cardinal invariant is small in the iterated Sacks perfect set forcing model, and that its corresponding parametrized diamond principle implies the existence of union ultrafilters. As a corollary, this establishes the existence of union ultrafilters in the iterated Sacks model of Set Theory.
Keywords
Cite
@article{arxiv.1706.00830,
title = {A parametrized diamond principle and union ultrafilters},
author = {David Fernández-Bretón and Michael Hrušák},
journal= {arXiv preprint arXiv:1706.00830},
year = {2018}
}
Comments
13 pages; final version as accepted for publication in Colloquium Mathematicum